1. Field of the Invention
The invention herein relates to a practical forged flange-type valve fabrication method that utilizes the blueprinted profiles of cast valves to forge one-piece or two-piece flange-type valves. In the practical forged fabrication method, the left and the right primary elements of one-piece or two-piece flange-type valves are delineated by the divisions of the neck sections and includes the forging the blanks of the left pipeline connection section of a one-piece flange-type valve and the structurally identical left and the right pipeline connection sections of a two-piece flange-type valve, the ball valve housing section of a one-piece flange-type valve, the plug, the ball valve housing section, and the ball valve position limiter section. External threads and water-tight gasket sleeves are respectively machined onto front outer sides and ends of the left pipeline connection section of a one-piece flange-type valve and the left and the right pipeline connection sections of a two-piece flange-type valve and internal threads are tapped in the left connection hole of the structurally identical ball valve housing sections of a one-piece or a two-piece flange-type valve as well as the right connection hole of the ball valve limiter section. The left pipeline connection section of the one-piece flange-type valve is structurally identical to the left and the right pipeline connection sections of the two-piece flange-type valve, such that the left connection hole of the ball valve housing section and the right connection hole of the ball valve position limiter section can be coated with a thread locking agent and tightly fastened together, which enables the left and the right pipeline connection sections of the one-piece or the two-piece flange-type valve to be interchangeable. In addition to maintaining the original strength and appearance of forging, the invention herein lowers production costs, reduces storage needs, lessens material waste, shortens the finishing time, and decreases defect rates,
2. Description of the Prior Art
Conventional flange-type valves include one-piece and two-piece flange-type valves that are generally all cast fabricated because the left and right primary elements can be cast as a single structural entity and, furthermore, most of the interior and exterior features of the said initial blanks are already formed after being cast into shape and only require the finishing and drilling of various sections to complete the valve. However, cavitation readily occurs during the casting process and to lessen the fine surface pitting resulting from the said cavitation, the initial blanks are given additional thickness to provide for interior and exterior finishing. While this reduces fine pitting, the removed constitutes an enormous waste and, furthermore, the complete elimination of the pitting is not possible. As a result, defect rates tend to increase and defective products that are marketed may leak. Soldering or welding during maintenance could unavoidably result in explosions or fires, which are common disasters often observed.
Due to the said shortcomings of ball valves that are fabricated by casting, the industry expected to avoid pitting flaws by forging the valve bodies. Referring to FIG. 1, the initial blank of a forged two-piece flange-type valve of typical manufacture achieved the objective of single-entity forming but still utilizes horizontal forging technology to forge the one-piece flange-type valve. The one-piece flange-type valve A requires the vertically oriented die removal angle B during fabrication to facilitate opening the die and, furthermore, the fabricated blank was solid and still requires hollowing out and drilling. Referring to FIG. 1-A and FIG. 1-B, the left water-tight gasket containment recess D2 and the right inverted angle D3 were formed in close proximity between the ball valve chamber D and the left passage D1, and then the left and the right water-tight gaskets were inserted into the left and the right water-tight gasket containment recesses D2 and F2. To enable the installation of the ball valve into the ball valve chamber D, the passage E had the same diameter as the ball valve and also required fastening the right external threads F1 of the plug F to the right internal threads E1 of the right passage E. Therefore, the right water-tight gasket containment recess F2 was formed on the end surface of the plug F and then the right water-tight gasket was inserted into the said right water-tight gasket containment recess F2 and rested against the ball valve. This is essentially how one-piece flange-type valves are still fabricated and the method has not undergone any alterations since inception. Compared to current forging approaches, the solid one-piece flange-type valve A requires complex and arduous machining and, furthermore, wastes substantial amounts of material that is reflected in greater production costs and the expensive price detracts from market competitiveness. Users are denied returns and have no alternative but to continue utilizing such cast valves that easily develop problems which often unavoidably lead to hazardous situations.
Referring to FIG. 2, the two-piece flange-type valve is forged as the left and right primary elements A1 and A2, but because of the limitations on easily opening the dies after forming, a die removal angle had to be included inside the die which left a vertically oriented border on the left and right primary elements A1 and A2 that was manifested in the die release angles A11 and A21. Furthermore, the required center passages as well as the ball valve chamber of the left and right primary elements A1 and A2 could not be formed at the same time. The left and right primary elements A1 and A2 were solid blanks that still required shaping to become a ball valve. For example, the area indicated by the invisible line in the left and right primary elements A1 and A2 had to be removed and, therefore, additional material had to be utilized in the shaping. Forging was followed by several stages of difficult finishing, which involved the waste of material. As such, although forging was expected to solve the shortcomings of casting such as high material and finishing costs, the problems encountered were the same as those of conventional one-piece flange-type valves and the cost remained high, the product did not impress users and could not be successfully promoted to consumers because improvement was still necessary.
Therefore, in view of the said shortcomings, the inventor of the invention herein addressed the said drawbacks by conducting research based on many years of production experience, with efforts finally culminated in the research and development of the invention herein.